Photographic transfer paper



Mar. 27, 1923,

H EGA$HIRA.

PHOTOGRAPHIC TRANSFER PAPER. HLED SEPT.18, 1919.

- Patented Mar. 27, 1923.

UNITED STATES PATENT OFFICE.

HARUKI EGASHIRA, OF TOKYO EU, JAPAN.

PHOTOGRAPHIC TRANSFER PAPER.

"Application filed September 18, 1919.

i To all whom it may concern.

Be it known that I, HARUKI EGASHIRA, a-

clare that the following is a full, clear, and

. exact description thereof, reference being had to the accompanying drawings, which form part of this specification.

This invention relates to a photographic transfer paper consisting of smooth paper coated with a thin transparent film formed by spreading upon the paper a solution of nitro-cellulose or any other cellulose ester,

and spreadin over the film thus formed a sensitive emulsion of a silver salt and gelatin.

The object of this invention is to obtain a photographic transfer paper which, when it is pasted upon any surface, leaves thereon the photographic lmage, covered with a transparent film of nitro-cellulose or the like, the paper being easily peeled off.

The present wide application of photography to industrial and artistic purposes demands a large supply of negative plates of large sizes, but they are very expensive.

In order to meet this growing demand so for large size plates cheaply, it has been proposed to use what is known as negative paper. According to this method, paper coated with a sensitive emulsion, is directly exposed in a camera; and after developing 36 and fixing the image, the paper is made transparentby soaking it. with wax or the like. However although the paper becomes transparent to'sight, its constitution not being changed and its fibres remaining the 40 same, the transmission of light is by no means uniform all over the paper, and consequently, it is impossible to print there-- from 7 clear positive pictures. Another method is to form a film of gelatin on paper and to coat the film with a sensitive emulsion. Then after exposing the paper and developing and fixing the image, the whole is pasted on glass or the like, and the paper is stripped off, thus leaving on the glass the filmof gelatin with the image fixed thereon.

However according to this method, thegelatin film sticks to the paper, and even when treated in warm water, it is not an'easy task to peel off the paper. Moreover gelatin films being very brittle, they arevery difii- Serial No. 324,448.

cult to handle, and this method is not of practical use.

The present invention is an improvement in the above processes, and the following is an example of carrying it into practice, reference belng had to the accompanying draw- 1ng The accompanying drawing shows a vertical section, much enlarged, of my transfer paper, part thereof represented therein being separated from the support. I spread evenly on a surface of smooth paper 3a thick solution of collodion, to form a thin, transparent and smooth layer 2 of nitro-cellulose by volatilizing the ether and the alcohol. In the dark room I then coat the nitrocellulose layer with a sensitive emulsion, the principal ingredients of which are silver bromid and gelatin, and' dry it thus forming a sensitive layer 1. Thus my invention is something like a common bromlde paper but has a film of nitro-cellulose between the paper and its sensitive film.

To use the transfer paper of my invention as a positive, it is exposed and the image is developed and fixed in the same manner as an ordinary dry plate. I then spread on glass or the like to which the photographic image is to be transferred a 3% solution of gelatin, and when dried, immerse it in water and place on it carefully the developed and fixed transfer paper. I then take the whole out of the water, and squeeze it and dry it slowly. When nearly dry, I peel off the paper, which comes off very easily leaving behind the photographic image covered with a transparent film of nitro-cellulose.

I am aware that before my invention there was known a photographic transfer paper consisting of a waxed paper coated with a substratum of a powdery nitro-cellulose deposited from an aqueous etheral alcoholic solution, on which a sensitive gelatin emulsion is spread, such as the one described in United States Patent -No. 1,299,479, Apr. 8, 1919, granted to Frank William Kent and Thomas Percy Middleton. However according to this process, a friable, rotten or porous substratum of powdery nitro-cellulose is formed upon a waxed paper, in order to avoid. the repellent nature of the waxed paper, thereby uniform coating thereof with a sensitive gelatin emulsion being made possible. The object of using nitro-oellulose in this process is, therefore quite different from that in my invention.

Moreover, in this ered by a transparent film. Therefore the above process is entirely different from my invention.

My transfer paper transferred to glass can be used as a negative and is just as good as any dry plate. When the transfer paper of this invention is used as a negative, it is pasted on a glass plate or the like, before exposure, and then it is stripped. The im-' age can be enlarged or reduced, and thus printing plates for collotype, offset, and the like, of any desired size can be manufactured by a very simple method. My transfer papers may also be used for printing positive images on them, and When such positive pictures are pasted on metallic plates, porcelain, Wood, bamboo, opalesoent board or the like, artistic and tasteful photographs Will be obtained. When such positive pictures are pasted on glass, they can be used for magic lanterns. Thus the application of the transfer paper of my invention is very Wide.

My photographic transfer paper is usuable in two Ways; to Wit, either as positive or as negative. When the transfer paper of this invention is used as a positive, it is pasted on other paper, glass, Wood plate, or porcelain plate, after the image is developed, and then it is stripped and transferred; when used as a negative, the transfer paper is pasted on glass plate or the like, before exposure, and then it is stripped.

Claims:

1. A photographictransfer paper comprising a smooth support paper, a layer of cellulose ester on the surface of the smooth paper, and a sensitive emulsion layer on the cellulose esterlayer, the emulsion layer and the cellulose layer together forming a film adapted to be separated as one from the support paper substantially as and for the purposes hereinbe-fore set forth.

2. A photographic transfer paper comprising a. smooth support paper, a layer thereon formed by applying a solution of cellulose ester to the surface thereof, and a sensitive emulsion layer on the cellulose ester layer; the two layers forming a film adapted to be separated from thesupport paper substantially as and for the purposes hereinbefore set forth.

3. A photographic transfer paper, comprising a smooth paper having a collodion layer and a layer of an emulsion of silver bromid and gelatin on said collodion layer; the tWo layers forming a film easily separable from the support paper, substantially as and for the purposes hereinbefore set forth. I

4. A'pho-tographic transfer paper consisting of a smooth surfaced paper; a layer of cellulose ester on the smooth surface of said paper formed by applying a solution of such ester to the paper and drying it; and a sensitive emulsion layer upon the nitrocellulose ester layer, formed by spreading a sensitive emulsion over the ester layer, after the latter is dried; the emulsion layer and the cellulose ester layer being separable together as one film from the paper, substantially as and for the purpose described.

5. A photographic transfer paper, consisting of a smooth support paper, a dried collodion solution layer thereon, and a layer of sensitive emulsion, having for its chief ingredients silver bromid and'gelatin on the collodion solution layer: the film formed by the collodion and the sensitive emulsion layers being easily separable from the sup-port paper, substantially as and for the purposes hereinbefore set forth.

6. The herein described method of making photographic transfer papers, consisting in applying a solution of cellulose ester to the surface of smooth paper to form a layer thereon, .then coating such layer in a dark room with a sensitive emulsion, the sensitive emulsion and the cellulose ester being separable as one'film from the support paper after development, substantially as and for the purposes hereinbefore set forth.

7. The herein described method of making photographic transfer papers, consisting in first coating smooth paper With a collodion solution, and after drying spreading .on the collodion layer a layer of a sensitive emulsion of silver bromid and gelatin, thereby forming a film, consisting of the collodion and sensitive emulsion layers, easily separable from the support paper, substantially as and for the purposes 'hereinbefore set forth.

as my own, I afiix m signature.

HA UKI EGASHIRA. 

